Journal of anesthesia
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Journal of anesthesia · Oct 2013
Ultrasound and electrical nerve stimulation-guided S1 nerve root block.
A selective lumbosacral nerve root block is generally is performed under X-ray fluoroscopy, which has the disadvantage of radiation exposure and the need for fluoroscopy equipment. In this study, we assessed the effectiveness of ultrasound and nerve stimulation-guided S1 nerve root block on 37 patients with S1 radicular syndrome. With the patient in a prone position, an ultrasound scan was performed by placing the probe parallel to the body axis. ⋯ After nerve block, decreased sensation at the S1 innervated region and pain relief was achieved in all patients. No significant difference was noted in the effect of the block between perineural and paraneural patterns. In conclusion, this technique provided reliable S1 nerve root block in patients with S1 radicular syndrome and minimized radiation exposure.
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Journal of anesthesia · Oct 2013
Effects of dexmedetomidine, midazolam, and propofol on acetylcholine release in the rat cerebral cortex in vivo.
Acetylcholine plays an important role as a neurotransmitter in the central nervous system with involvement in both sleep and arousal. Dexmedetomidine, midazolam, and propofol are widely used for sedation of patients in intensive care medicine. In this study, we have examined the effect of continuous administration of dexmedetomidine, midazolam, and propofol on acetylcholine release in the rat cerebral cortex, using an in vivo microdialysis technique. ⋯ Dexmedetomidine administration decreased acetylcholine release, but this finding was not statistically significant. From this study, midazolam and propofol but not dexmedetomidine significantly suppressed acetylcholine release in the cerebral cortex at sedative doses. Even though the righting reflex recovered almost the same after the cessation of drug administration, midazolam suppressed acetylcholine release longer than propofol.